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Hello Readers,
How many of you regularly use twitter? I guess most of you. Have ever worried about the security it is providing? You should read on if your answer is NO.

One of colleagues gave a quick demo a few days back to show how insecure the default twitter is. His demo proved that, any one sitting in same network as yours can easily hijack your twitter account and tweet on behalf of you. He was able to make it because twitter runs on http by default. Since it is http, all the data transfer will happen over wire in plain text format. So, any one in your network with a couple of  tools can spoof your MAC address can easily capture what you are sending over wire and get the twitter cookie(key for maintaining your twitter session) and tweet using your twitter account. The method that my colleague demonstrated is a simple hack any one with computer knowledge can execute it.

How to I make it secure:  Twitter provides a option to make your twitter account to use https(secure http) as default protocol. Making use of this will at least prevent your twitter account from this kind of silly hacks.

You can follow the below procedure to enable the https

• Logon to twitter account.
• Go to your profile tab and click on edit profile
• Go to Account section in your profile and check the box Always use HTTPS
• Click on Save and enter your password when prompted

• Now your twitter account is secured.

Do you like one liners in powershell? Here is the quick and easy way to start, stop, restart a service on remote computer. This doesn’t require PowerShell remoting. That means you can use it against any computer which has windows operating system installed.

So far I have authored two articles on managing services using powershell:

1. Start/Stop/Restart service on remote computer with powershell
2. PowerShell: Start and stop services on remote computer with alternate credentials

The first one I wrote when I was not matured enough with PowerShell and the second one recently to address a specific requirement where user need to pass alternate credentials to manage services.

As most system administrators love to use poweshell one-liners which avoids any external script/module invocation, I want to share this little one which starts, stops, and restarts a service on remote computer.

Start a service on remote computer:

Start-Service -InputObject $(Get-Service -Computer COMPUTER1 -Name spooler)

Stop a service on remote computer:

Stop-Service -InputObject $(Get-Service -Computer COMPUTER1 -Name spooler)

Restart a service on remote computer:

Restart-Service -InputObject $(Get-Service -Computer COMPUTER1 -Name spooler)

Hope these little ones helps.

The popularity of PowerShell is increasing day-to-day and now every System administrator want to say bye to their VB scripts and enter the powerful powershell world. A system administrator who is familiar with VB script(or has in home grown scripts in VB) want to try powershell, the first question he gets into mind is, “how to do xyz task in powershell”. Of course, we can ask our big brother google.com but it will take little long to find the powershell way of coding a task.

For those kind of admins, MS has published a long list of converting xyz from VB script to PowerShell. This pretty much enough for a person who wants to convert their VB scripts into powershell code. For your easy reference I am posting the content from MS technet site to here.

Hope this helps…

You might see the error message outlined in subject while installing/uninstalling software on windows 2003 computer by connecting to terminal services. We all know that application installation has certain limitations when it comes to terminal services (anyone know why?). In such cases if you still want to install/uninstall the application on these terminal services enabled servers, you need to choose one of the following methods.

If this the requirement is just one of the case, then option#1 best suits you.

Option#1:

start mstsc with /console or /admin option and then connect to the server. This allows you to connect to the console of the server directly eliminating terminal services piece from you way.

Go to start -> Run -> type “mstsc /admin /v:servername” and click OK if you are using RDP client v6 or above

Go to start ->Run -> type “mstsc /console /v:servername” and click OK if you are using legacy version of RDP client.

Option#2:

If your administrators are expected to install applications on servers by connecting via terminal services, then you need to make sure that application installation is allowed. You can do it via group policies.

“computer configuration” -> “administrative templates” -> “windows components” -> “windows installer” -> “allow admin to install from terminal server session” should be enabled

Hope this helps.

$file1version = [version](Get-Command .File1.dll).FileVersionInfo.FileVersion            

$file2version = [version](Get-Command .File2.dll).FileVersionInfo.FileVersion            

if($file1version -eq $file2version) {            

write-host "File version numbers are equal"            

} else {            

write-host "File version numbers are not equal"            

}

Above simple code compares file versions of two files. The comparison here is very straight forward. In the above code it first queries the file versions of two files, File1 and File2 and compares both of them to see if they are equal or not.

function Get-FileVersionInfo
{
  param(
    [Parameter(Mandatory=$true)]
     [string]$FileName)            

  if(!(test-path $filename)) {
  write-host "File not found"
  return $null
  }            

  return [System.Diagnostics.FileVersionInfo]::GetVersionInfo($FileName)
}

Above code is little bit enhanced which checks for file existence and returns the version numbers in object format which can be further used for other version control related operations.

Have you ever got a requirement to minimize all windows on the desktop using powershell script? It is helpful when you want to give a pop-up message to user which should draw their immediate attention.

I came across this little tip while exploring shell.application com object. It has other useful functions like undominimizeall, cascade windows, and many other explorer functions.

$shell = New-Object -ComObject "Shell.Application"
$shell.minimizeall()

You can also undo minimize all windows by using below code.

$shell = New-Object -ComObject "Shell.Application"
$shell.undominimizeall()

To see the clear functionality, add some delay between minimizeall() function and undominimizeall() function.

$shell = New-Object -ComObject "Shell.Application"
$shell.MinimizeAll()
start-sleep -Seconds 5
$shell.undominimizeall()

Hope this helps… You can explore more functions of shell.application object by using below code snippet.

New-Object -ComObject "Shell.Application" | gm | select Name, MemberType

Backup Procedure:

1. Go to Start -> Run and type “%appdata%MicrosoftSticky Notes” and Click “OK”
2. This opens the location of Sticky Notes file, “StickyNotes.snt”, where all the sticky notes data is stored.
3. Just take a copy of this file and save it somewhere safe.

Procedure to Restore:

Restoring Sticky notes is as good as copying back the file that you saved in safe location. Just copy the backed up file to “%appdata%MicrosoftStickyNotes” folder.

Hope this helps.

Today I got a requirement to convert a normal string with value “20100610″ to date format using powershell. I thought I will be able to do it easily with “Get-Date” cmdlet but it never happened that easy. After some searching, I figureout the way.

$strtime = “20100610″
[datetime]::ParseExact($strtime,”yyyyMMdd”,$null)

While doing the conversion from string value to date/time format, first you should know what you are trying to convert. The string in my case is a eight character string in which first 4 characters belongs to year(yyyy), the next two belongs to month(MM) and the remaining two belongs to date(dd). That is why I used yyyyMMdd format in the parseexact function.

Executing above code results in below output.

If you are not interested about time details in output, just make the code a bit complex like below.

([datetime]::ParseExact($strtime,”yyyyMMdd”,$null)).toshortdatestring()

I bought a new Cisco LINKSYS WRT120N wireless router and noticed that reset button is not working properly in it. That means if I press and hold the reset button to reset the router settings to factory defaults, it is not working. After some troubleshooting, I figured out the problem and fixed it. The solution here is to upgrade the firmware of the wireless router to latest version.

To do this, follow below steps.

1. Download latest firmware for WRT120N wireless router from Cisco site(http://homesupport.cisco.com/en-us/wireless/lbc/WRT120N ) and save to disk
2. Now takeout the router power -> Hold the reset button -> Connect the power
3. Now connect a network cable from your computer to port#1 of wireless router. To surprise you here, the LED#4 glows though you connected the cable to port#1. Don’t worry…. This is not much to bother
4. Open browser in your computer and go to http://192.168.1.1
5. A window appears asks you to input the firmware file. Here select the file and click on reset
6. This upgrades the firmware version to latest and now you can use the regular method for resetting the password to factory settings by holding the reset key. The reset key should work now as expected

Feel free to write in comments section if you have some questions.

Today I bought a wireless router from CTC, hyderabad, india. To purchase that I enquired the cost in multiple shops and prices are differing as usual from shop to shop. In one shop, he quoted very less amount compared to other shops in the market. While others are quoting INR 2600, this guy quoted 2000 only. Since the cost is less, I prepared to buy that and tried opening the box. The shop keeper immediately stopped and warned me that I cannot open it till I pay the money. I was shocked. This box doesn’t have any seal on it and I am sure the shop keeper would have opened N number of times before. But I don’t know why he is trying to impose such a restriction on customer. I told him that I will buy it and he is responsible if any item found missing in the box and he agreed for that. I opened the box but has suspicious feeling stuck somewhere in mind that this guy is trying to cheat me in some aspect. I purchased the wireless router and left the shop with these thoughts.

I reached home very late night and started my new wireless router setup. I read the installation manual property and there it is mentioned that by default router will not consist any username and the password is “admin”. I opened browser and connected to http://192.168.1.1 and enter the password “admin” with blank user name as instructed in manual. But it is not working. I tried multiple times but ended with same results. I tried few other default password combinations that I know but no help. Finally I decided to reset the router to factory default settings.

The reset to factory settings involves holding the reset button for 30-60 seconds and restarting the router. I did it and tried to enter in with default credentials, but still not working. I tried multiple times with different pen tips, needles, etc to hold the reset button but in vain. Now I realized why that the shop keeper offered it for less price. I suspect someone returned it back because of some problem. That could be the reason I failed to enter in with default credentials as previous purchaser might had set the password of his choice.

So, now I am in a situation where either I don’t know the current credentials to login to the router or not in a position to reset to the default settings.

In this situation, my only available option is to return the device to vendor and demand for explanation and replacement. Before to that, I want to use my sysadmin skills to see if I can fix this issue myself — so started researching in internet.

After reading some posts and forum threads, I realized that reset button by default has problems in Cisco LINKSYS WRT120N model wireless routers and only option is to upgrade the firmware to latest version which fixes the reset button functionality. I downloaded the latest firmware from internet and installed on the device and I am able to take the device to factory default settings now J

Now I have mixed feelings. One way I am happy that I fixed the problem myself and other way I am sad that I was cheated by the shop keeper. Anyways, I love to troubleshoot, understand and fix the problems — I am thankful to the bloody shop keeper for giving such wonderful chanceJ.

 In my next posts, I will write about “how to make reset button working in ‘Cisco LINKSYS WRT120N’ wireless router” and “How to reset ‘Cisco LINKSYS WRT120N’ router password to factory settings”

This ends by rambling. Happy learning….